steel column with the geometry of a greek cross
steel column with the geometry of a greek cross
(OP)
Hi,
I've been suggested to use a steel column with the following geometry

This is a greek cross geometry and it was used by Mies Van Der Rohes in Barcelona Pavilion.
I thougt about doing it with 6 "L" shaped beams but I'm not sure the finish will polished between each shaped beam.
But the really relevant question is the safety design of it. The eurocode 3 shows how to determine the class of a single "L" beam and other singular elements, but that's as far as it goes.
Has anyone had this kind of trouble?
I've been suggested to use a steel column with the following geometry

This is a greek cross geometry and it was used by Mies Van Der Rohes in Barcelona Pavilion.
I thougt about doing it with 6 "L" shaped beams but I'm not sure the finish will polished between each shaped beam.
But the really relevant question is the safety design of it. The eurocode 3 shows how to determine the class of a single "L" beam and other singular elements, but that's as far as it goes.
Has anyone had this kind of trouble?






RE: steel column with the geometry of a greek cross
This should be analyzed as a cruciform column, which used to be a fairly common shape as it has flanges on four sides allowing for easy connection of beams to the column. It has an unusual failure mode of flexural-torsional buckling. A google search of cruciform columns will likely turn up a lot of details and research. Not sure what the eurocode has regarding it but if it's like the AISC then there are likely provisions for it.
Professional and Structural Engineer (ME, NH)
American Concrete Industries
www.americanconcrete.com
RE: steel column with the geometry of a greek cross
I tested my model with a HE 120B section from arcelor mittal and it was safe.
Therefore:
The dimensions fit perfectly. And like I've read before, if it's stupid but it works, it ain't stupid :)
What do you think?
RE: steel column with the geometry of a greek cross
The more typical way I've seen cruciform columns created is welded tee shapes to the web:
Professional and Structural Engineer (ME, NH)
American Concrete Industries
www.americanconcrete.com
RE: steel column with the geometry of a greek cross
Also I've never seen that kind of cross section, I've just run trough the arcelor sales program, and couldn't find such kind of beam.
Thanks for your help :)
RE: steel column with the geometry of a greek cross
https://sydney.edu.au/engineering/civil/publicatio...
http://www.newsteelconstruction.com/wp/wp-content/...
Check as well paragraph 6.3.1.4 of EN1993-1-1.
RE: steel column with the geometry of a greek cross
RE: steel column with the geometry of a greek cross
Professional and Structural Engineer (ME, NH)
American Concrete Industries
www.americanconcrete.com
RE: steel column with the geometry of a greek cross
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: steel column with the geometry of a greek cross
I have a long slab with 13 m that has 4 columns on its extremity, and is partially supported by 2 walls on the extremity. (The concrete walls are below the blue marks)
The problem so far is finding a cross section with such geometry that when cut will be compatible with a "L" section. To create a perfectly simetrical cross, something like this would have to happen
This means the web would have to be 3x the flange, or maybe I'm doing something wrong, I'm not sure.
But if it's really like this, there's no profile with such geometry
Edit: I think I'll probably will have to cut 2 "I" sections in half and get 4 "T" sections that dont meet at the end. That way I could get 1/4 of the load on each T member, and analyse each one individually wich would be simple.
This is also what I understand from the image on the first post. It would make the analysis simpler, but I'm not sure if the fact they don't meet at the end makes my load assumption wrong. For example, the T element on the inner side of the slab, would surely have more load than the one in the extremity.
RE: steel column with the geometry of a greek cross
RE: steel column with the geometry of a greek cross
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: steel column with the geometry of a greek cross
Thanks everyone for the tips :)
RE: steel column with the geometry of a greek cross
Now, be ready to work a little harder to paint that inside space.
Actually, the WF + doubled WT does look elegant, looks "clean" and does NOT look like a piece of "ugly, plain-old-structural steel" Plus, it can be welded with a simple jig and frame. The welds do not need to be continuous, but a staggered weld is a bit more difficult to calculate. Then again, you only need to calculate it once.
A WF can be split fairly easily into WT's, but find out if buying them separately as WT is actually going to be cheaper - Many places purchase WF, then cut them in half to sell you WT's that you could have cut yourself.
RE: steel column with the geometry of a greek cross